For many years now the most effective drugs against malaria have been derived from the Chinese plant, Artemisia annua. It is also known as sweet wormwood.

In 2009 researchers found that the most deadly species of malaria parasites, spread by mosquitoes, were becoming more resistant to these drugs in parts of western Cambodia.

This new data confirms that these Plasmodium falciparum parasites that are infecting patients more than 500 miles away on the border between Thailand and Burma are growing steadily more resistant.

The researchers from the Shoklo Malaria Research Unit measured the time it took the artemisinin drugs to clear parasites from the bloodstreams of more than 3,000 patients. Over the nine years between 2001 and 2010, they found that drugs became less effective and the number of patients showing resistance rose to 20%.

Prof Francois Nosten, who is part of the research team that has carried out the latest work, says the development is very serious.

“It would certainly compromise the idea of eliminating malaria that’s for sure and will probably translate into a resurgence of malaria in many places,” he said.

‘Untreatable malaria’

Another scientist involved with the study is Dr Standwell Nkhoma from the Texas Biomedical Research Institute.

“Spread of drug-resistant malaria parasites within South East Asia and overspill into sub-Saharan Africa, where most malaria deaths occur, would be a public health disaster resulting in millions of deaths.”

The scientists cannot tell if the resistance has moved because mosquitoes carrying the resistant parasites have moved to the Burmese border or if it has arisen spontaneously among the population there. Either way the researchers involved say it raises the spectre of untreatable malaria.

“Either the resistance has moved and it will continue to move and will eventually reach Africa. Or if it has emerged, now that artemisinin is the standard therapy worldwide then it means it could emerge anywhere,” Prof Nosten told the BBC.

“If we were to lose artemisinin then we don’t have any new drugs in the pipeline to replace them. We could be going back 15 years to where cases were very difficult to treat because of the lack of an efficacious drug.”

Artemisinin is rarely used on its own, usually being combined with older drugs to help fight the rise of resistance. These artemisinin based combination therapies are now recommended by the World Health Organization as the first-line treatment and have contributed substantially to the recent decline in malaria cases in many regions.

Prof Nosten says the current spread of resistance could be similar to what happened in the 1970s with chloroquine, a drug that was once a front-line treatment against the disease.

“When chloroquine resistance reached Africa in the middle of the 1970s it translated into a large increase in the number of cases and the number of children who died increased dramatically.”

In a separate paper published in the journal Science researchers have identified a region of the malaria parasite genome that is linked to resistance to artemisinin.

Dr Tim Anderson, from Texas Biomed who led this study, says that while mapping the geographical spread of resistance can be challenging it may be hugely beneficial.

“If we can identify the genetic determinants of artemisinin resistance we should be able to confirm potential cases of resistance more rapidly. This could be critically important for limiting the further spread of resistance.”

According to the World Malaria Report 2011 malaria was responsible for killing an estimated 655,000 people in 2010 – more than one every minute. A majority of these were young children and pregnant women.

Depression is the most common psychiatric disorder among HIV-positive people, Photo: Eva-Lotta Jansson/IRIN

ADDIS ABABA, 7 December 2011 (PlusNews) – HIV patients in Africa frequently suffer shame and depression but the continent’s health systems are ill-equipped to handle the issue, which not only affects their quality of life, but can lead to poor adherence to HIV treatment regimens.

While HIV programmes focus heavily on reducing externalized stigma and ill-treatment of HIV patients by society, little is done to deal with a patients’ self-perception and how that might deteriorate following an HIV diagnosis, speakers said at a session on stigma at the 16th International Conference on AIDS and Sexually transmitted infections in Africa in Addis Ababa.

Studies show that depression is the most common psychiatric disorder among people living with HIV, and is more prevalent among HIV-positive people than the general population.

“Operational research carried out in Zambia has found a positive correlation between patients who self-stigmatized and failure to adhere to treatment,” said Sikazwe Izukanyi from Zambia’s Ministry of Health. “Self-stigma was often found in patients who did not disclose their status to partners or family members – making it difficult to maintain strict adherence to regimens while trying to hide the drugs.”

Izukanyi noted that while counselling was a standard part of HIV care in Zambia, counsellors needed to be made aware of the prevalence of self-stigma and how to deal with it.

A 2010 Ugandan study by Makerere University found that HIV-positive patients were more critical of themselves, had significantly greater problems making decisions, poorer sleep, tired more easily, experienced more appetite changes and had more cognitive impairment.

ARVs and self-stigma

According to a study by Yordanos Tiruneh, an Ethiopian academic with US-based Northwestern University, antiretroviral (ARV) therapy has been key to reducing external stigma by minimizing the visibility of physical imperfections and restoring functional daily activities such as the ability to work. The study, which used 105 interviews with Ethiopian men and women on ARVs, also found that the support networks formed by people living with HIV gave them much-needed social capital.

However, according to Yordanos, while ARVs were linked to a reduction in external stigma, the study found that they tended to increase internalized stigma, sometimes resulting in failure to properly adhere to ARVs.

“When I think of the two tablets that keep me alive, I hate myself and I feel that I am dead,” one of the study’s interviewees is quoted as saying. “Sometimes I get furious to see myself like a walking corpse, and other times I see myself as a doll that functions with a battery. I would say, without these batteries [pills], I am nothing.”

According to a US study, adherence to ARVs was higher in patients for whom anti-depressants were prescribed.

A severe shortage of mental health professionals in Africa means that HIV-associated depression is largely ignored. For instance, according to the UN World Health Organization, Burundi has just one psychosocial care provider per 100,000, against a target of at least eight, while Ethiopia has less than one, against a similar target.

“The problem is largely a human resources one; while strengthening health systems, governments should remember to focus on mental-health issues,” said Izukanyi. “As it is, we have no systems for screening, diagnosing and treating patients with mental-health issues.”

Among other things, experts recommend integrating mental-health services into primary healthcare activities, developing mechanisms to ensure a good supply of psychotropic medication and more research into mental-health issues in Africa.

GENEVA — The Western Black Rhino of Africa has been declared officially extinct, and two other subspecies of rhinoceros are close to meeting the same fate, a leading conservation group said Thursday.

The International Union for Conservation of Nature said a recent reassessment of the Western Black Rhino had led it to declare the species extinct, adding that the Northern White Rhino of central Africa is now “possibly extinct” in the wild and the Javan Rhino is “probably extinct” in Vietnam, after poachers killed the last animal there in 2010.

A small but declining population of the Javan Rhino survives on the Indonesian island of Java, it added.

“A lack of political support and willpower for conservation efforts in many rhino habitats, international organized crime groups targeting rhinos and increasing illegal demand for rhino horns and commercial poaching are the main threats faced by rhinos,” the group said in a statement accompanying the latest update of its so-called Red List of endangered species.

About a quarter of all mammals are at risk of extinction, IUCN said, adding that some species have been brought back from the brink with successful conservation programs.

The Southern White Rhino numbered just 100 animals at the end of the 19th century, but has since flourished and now has a population of over 20,000.

The Przewalski’s Horse, a type of wild horse from Central Asia, has come back from extinction after a successful breeding program in captivity.

The Red List now contains almost 62,000 species of plants and animals, whose status is constantly monitored by conservationists.

ATLANTA — The quest for the world’s first malaria vaccine appears to have taken a big step: A study in Africa shows experimental shots cut the risk of disease in young children by half.

The initial results from a final stage of vaccine testing were released Tuesday, and the vaccine’s developers called it a milestone in helping to tame one of the world’s most devastating killers.

However, the vaccine won’t be available for at least three years, as crucial further testing must be completed to see how well it works in infants and how long protection lasts. Then the vaccine must be reviewed by government agencies in Europe and in individual African countries.

“We still have a way to go,” Tsiri Agbenyega, lead researcher for the African study, said in a conference call with reporters.

The early results show the vaccine is only about 50 percent effective, significantly lower than the protection seen in more common vaccines. But some experts said it’s a vast improvement over the current situation, and could still save hundreds of thousands of lives.

Globally, malaria kills nearly a million people annually. More than 90 percent of them live in Africa, and most are young children and pregnant women.

Scientists have been trying for decades to develop a malaria vaccine and the one tested – developed by GlaxoSmithKline – is furthest along. Without a vaccine, efforts have concentrated on malaria drugs and other ways to prevent infection such as mosquito bed netting and insecticides.

The new vaccine targets a malaria parasite found in sub-Saharan Africa. Malaria spreads through mosquitoes, which bite people and flush malaria parasites into the bloodstream. The parasites cause bouts of high fever and can end in fatal organ failure.

In the United States, malaria has been eradicated since the early 1950s. Only about 1,500 cases are diagnosed in the U.S. each year, most of them travelers or immigrants from South Asia, sub-Saharan Africa or other places where malaria commonly spreads.

The new study – still under way – began in 2009 and involves more than 15,000 children in Burkina Faso, Gabon, Ghana, Kenya, Malawi, Mozambique and Tanzania.

The results focus on about 6,000 children ages 5 to 17 months. A year after three doses, the vaccinated children had about half as many cases of malaria as a group that didn’t get the vaccine.

Meanwhile, experts are waiting for results from research in a younger group – infants ages 6 to 12 weeks. That’s the age when children in sub-Saharan Africa are vaccinated against other diseases. Earlier vaccination also affords earlier protection.

Although there are an array of vaccines against viruses and bacteria, there has never been an effective vaccine against a parasite, which is a more complicated organism. Adding to the complexity is there are five species of malaria parasites – the new vaccine is designed specifically to protect against the deadliest one, which is common in sub-Saharan Africa.

GlaxoSmithKline paid for the study along with the PATH Malaria Vaccine Initiative, a program funded by the Bill & Melinda Gates Foundation. The results were released Tuesday at a malaria conference in Seattle and published by the New England Journal of Medicine.

Details were still sketchy, but the U.S. Air Force’s Joint Space Operations Center and NASA say that the bus-sized satellite first penetrated Earth’s atmosphere somewhere over the Pacific Ocean. That doesn’t necessarily mean it all fell into the sea. NASA’s calculations had predicted that the former climate research satellite would fall over a 500-mile swath.

The two government agencies say the 35-foot satellite fell sometime between 11:23 p.m. EDT and 1:09 a.m. EDT. NASA said it didn’t know the precise time or location yet.

Some 26 pieces of the satellite – representing 1,200 pounds of heavy metal – were expected to rain down somewhere. The biggest surviving chunk should be no more than 300 pounds.

The Upper Atmosphere Research Satellite is the biggest NASA spacecraft to crash back to Earth, uncontrolled, since the post-Apollo 75-ton Skylab space station and the more than 10-ton Pegasus 2 satellite, both in 1979.

Russia’s 135-ton Mir space station slammed through the atmosphere in 2001, but it was a controlled dive into the Pacific.

Before UARS fell, no one had ever been hit by falling space junk and NASA expected that not to change. NASA put the chances that somebody somewhere on Earth would get hurt at 1-in-3,200. But any one person’s odds of being struck were estimated at 1-in-22 trillion, given there are 7 billion people on the planet.

Researchers are to expand a clinical trial of a new malaria vaccine after promising results in a preliminary study in Burkina Faso.

The trial was designed to test safety, but researchers found that vaccinated children had high levels of protection.

Described as a “most encouraging” result, a larger study involving 800 children is now to take place in Mali.

The scientists involved say they are hopeful that the vaccine will ultimately be very cheap to produce.

Around a hundred different malaria vaccine candidates have been developed to date but the MSP3 vaccine tested in Burkina Faso is only the second one to show a substantial level of protection against the illness.

The randomised, double blind study involved 45 children. It set out to test the safety of the vaccine but this follow up study found that children who received it had an incidence of the disease three to four times lower than children who did not.

Initially the children were split into three groups, with two of them receiving the experimental malaria vaccine developed by Dr Pierre Druilhe at the Pasteur Institute in Paris.

“Those two groups had very similar types of immune response, elicited by the vaccine, and the protection is almost identical, so it reinforces the confidence despite the fact that we are still dealing with a small group,” he said.

The vaccine is based on the fact that some adults in Africa acquire immunity because they are constantly exposed to the disease.

Early days

Dr Druilhe and his team discovered a key protein, MSP3, which provokes the body into producing antibodies that kill the parasite.

He said the protein is unique as it does not change much between different strains of the plasmodium parasite that causes malaria. This is believed to be a critical factor in developing an efficient vaccine.

He added: “We performed a large number of epidemiological studies that confirm that there was an association between that vaccine candidate and acquired protection, so when you immunise with this molecule you indeed induce protection.”

Another scientist involved with the Burkina Faso study was Dr Louis Miller, the former head of the Malaria Vaccine Branch of the US National Institutes of Health.

He said: “I was always in favour of this approach as it offered a chance in a field with few successes. I found the results of this preliminary study in Burkina Faso to be most encouraging.”

High transmission

Encouraged by the early results, Dr Druilhe said the trial has now been expanded to 800 children in Mali. But he remains cautious.

“There have been too many claims of effective vaccines so we have to remain very cautious. It has to be confirmed and we have started on work to do that confirmation. Essentially the trial in Mali is about 20 times larger, in extremely high transmission conditions, so it should yield very clear cut results – this will be black and white.”

The other vaccine candidate that has shown success against malaria is called RTS, S. It has been funded by the Bill and Melinda Gates Foundation and is set to go into production with pharmaceutical giant, GlaxoSmithKline.

But there are concerns that it could be expensive, especially for people in Africa and other regions affected by the disease.

Dr Druilhe says his vaccine could be a lot cheaper – perhaps half a dollar or less a bottle.